1. Technical Field
This invention generally relates to a finding apparatus and in particular it relates to a sonic beacon for use by archers in locating their arrows without alarming any prey.
2. Background Art
Archery hunters oftentimes spend as much or more time hunting for lost arrows as they spend hunting for their prey. Consequently, several attempts have been made to develop devices to aid hunters in finding their arrows. Generally, the devices are divided into two categories, those employing radio transmitters on the arrows and those employing audible transmitters on the arrows. To date, neither have found significant acceptance.
The radio direction finding technology has seen fairly limited use. For the average archer, radio direction finding arrow locators have proven expensive, inefficient, and generally too complex for anyone less than a ham radio operator to operate. However, one major advantage that the radio transmitters have over their audible counterparts is that the radio transmitters are silent and therefore do not frighten the game away. The idea of not frightening game away is most important when the hunter has missed his or her first shot. Any noise which is not natural will tend to scare the prey away. Having a beacon which is silent won't alarm the prey and thereby allow the hunter to get a second shot off.
A typical arrow finding transmitter is taught in Robinson et al., U.S. Pat. No. 4,675,683. Robinson et al. teaches a miniature transmitter housed in a cylindrical housing which is coextensively attached between the arrow head and arrow shaft. The transmitter advantageously uses the metallic arrow shaft as the radiating element of the antenna.
Sloan et al., U.S. Pat. No. 3,336,530, teaches a direction finding receiver for use with Robinson arrow transmitter. The receiver taught by Sloan is intended for receiving a modulated signal and uses a bi-directional loop antenna. Loop antennas are known to have a limited range and are very susceptible to reflective wave reception. Sloan teaches a direction finding system whose range is limited to about a quarter of a mile on relatively flat terrain.
A second radio transmitter equipped arrow is taught by Boy U.S. Pat. No. 4,704,612. However, Boy teaches using an inertia activated switch to activate the transmitter circuit. The obvious advantage is the power saving feature realized by not having the circuit energized prior to impact. However, the inertia switch is a momentary switch and consequently, additional circuitry is necessary to provide continued activation of the circuit.
A prior audible transmitting arrow locator is taught in U.S. Pat. No. 4,421,319 to Murphy. This patent teaches the use of an arrow nock having a hollow cavity which houses a miniaturized electronic buzzer being energized after a pre-selected time delay by a timing circuit such as a 555 timing IC. The signal emitted from the device is very foreign to the environment and often scares the game away from the area. Additionally, depending on the type of game being hunted, oftentimes the hunter must nock the arrow on the bow string and draw it into a shooting position, holding it there for several minutes before he is able to shoot. Obviously, if the hunter activates the timer when he nocks the arrow as Murphy teaches, the timer could very well time out and activate the buzzer before the arrow has even been released, scaring the game away.
What is needed is an arrow locator which exhibits the low cost, compact, and ease of use features of the prior art audible transmitters and at the same time also doesn't scare potential pray away by emitting a conspicuous signal. It is therefore an object of the present invention to provide an arrow with a small inexpensive audible beacon which is activated upon impact and which emits an audible signal which mimics a naturally occurring sound to aid in the location of the archer's arrows and possibly allow the hunter to get a second shot or shots off.